Interface agent for plastering mortar and wall surface treatment process before and after plastering mortar construction

The invention discloses an interface agent for plastering mortar and a wall surface treatment process before and after plastering mortar construction. The interface agent for plastering mortar is prepared from the following raw materials in percentage by weight: 30 to 50 weight percent of cement, 2 to 4 weight percent of silica fume, 23 to 28 weight percent of limestone powder, 25 to 35 weight percent of fine sand, 0.08 to 0.12 weight percent of water-retaining thickening agent, 1.4 to 1.8 weight percent of polymer latex powder, 0.003 to 0.005 weight percent of internal curing agent and 0.03 to 0.06 weight percent of hollow fiber. By means of the internal curing agent and the hollow fibers in the interface agent, the problems that the water demand is increased, plastic cracking occurs, the strength is reduced and powder falls off due to the fact that only the internal curing agent is added into plastering mortar are solved; according to the process, the defect of wall plastering cracking can be thoroughly ove